DevBuddy: Offline Dev Toolkit

DevBuddy is an offline developer toolkit with 27 utilities for everyday coding, debugging, and API work. No accounts, no cloud round-trips. Everything runs on your phone.

WHY OFFLINE

- Paste sensitive tokens, payloads, and secrets without sending them anywhere

- Works on flights, in tunnels, behind strict firewalls

- Nothing logs, nothing syncs, nothing leaves the device

WHAT'S INSIDE — 27 TOOLS

Formatters

- JSON formatter and validator

- XML formatter

- SQL formatter

- Markdown preview

- Diff tool with line-level compare

Encoders and Decoders

- Base64 encoder and decoder

- URL encoder and decoder

- HTML entity encoder and decoder

- JWT decoder (header, payload, signature)

- Markdown to JSON

- API payload explorer

Generators

- UUID generator (v1, v4)

- Hash generator (MD5, SHA-1, SHA-256, SHA-512)

- QR code generator

- Lorem ipsum generator

- Prompt template builder

Converters

- Unix timestamp converter (epoch, ISO, human-readable)

- Color picker (HEX, RGB, HSL)

- Number base converter (binary, octal, decimal, hex)

- YAML to JSON converter

- Text chunker for prompts and RAG workflows

Testers

- Regex tester with live match groups

- Token counter

- AI safety checker

Security

- TOTP tester for 2FA codes

- AES encrypt and decrypt

- HMAC generator and verifier

MADE FOR

- Developers and software engineers

- QA engineers and API testers

- DevOps and SREs on call

- Students learning JSON, regex, JWT, hashes

- Technical writers and prompt engineers

COMMON TASKS

- Pretty print and validate a JSON response

- Decode a JWT to inspect claims and expiry

- Test a regex against sample input with live highlighting

- Generate a UUID or strong hash for a quick script

- Convert a Unix timestamp during incident triage

- Encode or decode base64, URLs, and HTML entities

- Format SQL or XML before pasting into a ticket or PR

- Generate a QR code from any text or URL

- Verify a TOTP code against a shared secret

- Encrypt or decrypt text with AES, sign with HMAC

DARK MODE

DevBuddy runs in dark mode by default and follows your system theme.

LANGUAGES

Available in 14 languages: English, Hindi, Spanish, French, German, Portuguese, Arabic, Bengali, Indonesian, Japanese, Korean, Russian, Turkish, and Chinese.

PRIVACY

DevBuddy does not collect your inputs. Every tool runs locally on your device. No telemetry on tool content.